We need to mirror logic in move_ptes() wrt need_rmap_locks to get proper
serialization file THP.
Signed-off-by: Kirill A. Shutemov <kirill.shute...@linux.intel.com>
---
mm/mremap.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
diff --git a/mm/mremap.c b/mm/mremap.c
index 3fa0a467df66..88fa7ab1a8ce 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -192,17 +192,27 @@ unsigned long move_page_tables(struct vm_area_struct *vma,
break;
if (pmd_trans_huge(*old_pmd)) {
if (extent == HPAGE_PMD_SIZE) {
+ struct address_space *mapping = NULL;
+ struct anon_vma *anon_vma = NULL;
bool moved;
- VM_BUG_ON_VMA(vma->vm_file || !vma->anon_vma,
- vma);
/* See comment in move_ptes() */
- if (need_rmap_locks)
- anon_vma_lock_write(vma->anon_vma);
+ if (need_rmap_locks) {
+ if (vma->vm_file) {
+ mapping =
vma->vm_file->f_mapping;
+ i_mmap_lock_write(mapping);
+ }
+ if (vma->anon_vma) {
+ anon_vma = vma->anon_vma;
+ anon_vma_lock_write(anon_vma);
+ }
+ }
moved = move_huge_pmd(vma, new_vma, old_addr,
new_addr, old_end,
old_pmd, new_pmd);
- if (need_rmap_locks)
- anon_vma_unlock_write(vma->anon_vma);
+ if (anon_vma)
+ anon_vma_unlock_write(anon_vma);
+ if (mapping)
+ i_mmap_unlock_write(mapping);
if (moved) {
need_flush = true;
continue;
--
2.8.0.rc3
